1. Field of the Invention
The present invention relates to exhaust gas purification systems, and more particularly to an exhaust gas purifying system and a method for purifying exhaust gas of combustion engines wherein the exhaust gas of the engine is passed through a spray of scrubbing liquid.
2. Description of the Prior Art
The combustion of a petrochemical fuel in combustion engines generally involves the reaction of air with various hydrocarbons which comprise the fuel. As air is chiefly comprised of oxygen and nitrogen gasses, the resultant products include oxides of nitrogen and carbon and unburned hydrocarbons, the latter generally comprising particulate matter contributing to what is generally referred to as “smog”. As petroleum based fuels generally contain sulfur, oxides of sulfur are typically also present in the combustion products.
The oxides of carbon are carbon monoxide and carbon dioxide. Carbon monoxide is undesirable as it is poisonous. Carbon dioxide is undesirable as it is a “greenhouse gas” generally thought to be a primary contributor to global warming.
Pollution from the exhaust of motor vehicles has caused serious air quality problems, especially in populated areas with heavy traffic. Such pollution has caused the “greenhouse” effect, and the pollution and toxic particles from such exhaust is everywhere. Vehicle exhaust is one of the major causes of such poor air quality, especially in large cities.
Many countries have adopted different policies and restrictions on vehicles in order to improve the air quality, such as using unleaded gasoline, low-sulphur diesel fuel and requiring the use of catalytic converters in an exhaust system of the engine.
In the conventional system for purifying exhaust gas, the catalytic converter, for example, is provided on an intermediate part of an exhaust system of the engine so that CO, HC and NOx as harmful components contained in the exhaust gas can be reduced. However, the catalytic converter only reduces the amount of the nitrogen oxides, unburned hydrocarbons and carbon monoxide, it produces nitrous oxide or laughing gas believed to be 300% more harmful than carbon monoxide, and does not have the function for collecting carbon as a harmful component contained in the exhaust gas discharged from the motor vehicles. Accordingly, even with the use of a catalytic converter a significant pollution problem still exists as catalytic converter works only when it becomes hot. Thus, there is a need for an exhaust gas purifying system and method that would significantly reduce the amount of carbon dioxide emitted to the atmosphere, neutralize acids present in exhaust gasses, and remove particulate matter (“smog”) from exhaust gasses.